This invention relates to control units suitable for heating systems, and systems embodying such units.
A heating system supplying an environment often needs to be controlled in relation to the temperature of another environment, for example to maximize efficiency, or to maximize thermal loss or unwanted temperature differences. Also, it may be required to control the temperature of one environment to provide a fixed temperature differential between that and another environment, or between one environment and several others, or between various environments with various differentials related one to another. These, and related control operations, require control decisions at decision points within the control system relating to the activation of equipment to produce heat in a particular environment, or to transfer heat between environments.
The object of the invention is to provide an improved control unit for a heating system, which operates in dependence on the differential between two sensed temperatures and enables the differential to be maintained within close limits, and which is capable of a decision-making function in respect of output control.